On Sunday, South America’s power blackout, which affected over 50 million people, raised questions about the stability and security of the power infrastructure in Argentina.
Argentina, which has a population of 45 million, was the country most affected by the outage that started at around 7am local time (10:00 GMT).
The blackout affected neighbouring Uruguay and spilt
Authorities expect to understand the actual cause of the outage over the next two weeks, as an investigation moves forward into the cause of the blackout.
The power blackout stopped transit systems for a few hours and forced authorities to scramble to complete local elections, raising questions about why the blackout occurred and how to prevent it from happening again in the future.
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Argentina said it isn’t ruling out a cyberattack after what President Mauricio Macri called an “unprecedented” power blackout struck the region.
Though a cyberattack isn’t the primary hypothesis, it can’t be ruled out, Argentine Energy Secretary Gustavo Lopetegui told reporters in Buenos Aires.
A “technical issue” or simple humidity could have triggered the breakdown, said Carlos Garcia Pereira, head of Transener, Argentina’s largest power-transmission operator.
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“This morning, a fault in the coastal transmission system caused a power outage in the entire country whose cause we cannot yet determine precisely,” Macri said in a series of comments on Twitter. “This is an unprecedented case that will be thoroughly investigated.”
The blackout delayed voting Sunday in gubernatorial elections in Argentina’s provinces of Santa Fe, Formosa, and San Luis. Voters marked ballots by candlelight or using their mobile phones as flashlights amid an “emergency protocol,” newspaper Clarin reported.
Gubernatorial elections in Tierra del Fuego in the south were unaffected by the outage because the province is separate from the rest of the country’s grid.
South America's distribution network
Authorities started restoring power by mid-afternoon on Sunday even without fully knowing what caused the outage, reported Al Jazeera.
Experts are looking more deeply for answers by studying a powerline that transports energy from the two major dams of Yacyreta and Salto Grande to the capital of Buenos Aires.
Yacyreta is a combined dam and hydroelectric plant that is shared by Argentina and Paraguay. It generates 13.8% of Argentina's total electricity supply, making it one of the most important sources of power.
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The Salto Grande power plant, shared by Argentina and Uruguay, supplies 4% of Argentina's electricity but 44% of the electricity in Uruguay – a much smaller country with a population of less than 4 million.
"The interconnection between Yacyreta and Salto Grande failed, and that made the whole system collapse," said Gonzalo Casaravilla, the CEO of Uruguay's state power company, through a corporate Twitter account.
"We've been interconnected with Argentina for 40 years and nobody remembers this to have happened before."